Ventilator for truck covers



June 7, 1938. w. F. CRAWFORD VENTILATOR FOR TRUCK COVERS Filed Aug. 4, 1937 W- FZ CRAWFORD Patented June 7, 1938 UNITED STATES PATENT OFFICE Claims.

This invention relates to the art of ventilating and in particular to forced draft ventilation for the interiors of carrier vehicles employed in the transportation of passengers or merchandise in 5 which the load carrying portion is enclosed by a heavy fabric cover impervious to the passage of air and water.

It is well known that the forward motion of a vehicle of this character creates a strong suction at the rear end which not only constitutes a definite hindrance to the progress of the vehicle that is reflected in fuel consumption or power de mand increase, but which sucks into the vehicle interior the highly toxic and deleterious exhaust l5 gases where the vehicle is propelled by an internal combustion engine. Also, road dust and dirt are sucked in, to the discomfort of passengers and to the actual detriment of merchandise or perishable goods susceptible to the harmful ef- 0 fects of such foreign matter.

An object of the present invention is to provide in an enclosed vehicle, ventilating means so related to the enclosing structure as to create under the influence of forward motion of the vehicle a forced or positive rearwardly directed air draft throughout the vehicle interior, and which is released at the rear end thereof in a manner to eliminate the possibility of formation of a vacuum which could give rise to the aforementioned objectionable rear end suction.

. Another object is to provide in a flexible truck body cover, ventilating means inherently capable of maintaining a passageway unobstructed to the free flow of air therethrough while at the same time preventing the passage of rain, snow or sleet.

A further object is to provide a flexible cover for truck bodies and the like, having ventilating apertures provided with interior air current forming deflector means whereby to impart any de- 4:0 sired directional air flow within the area encompassed by the cover when in service.

Other objects will be apparent from the description.

The present disclosure comprises an embodiment by which the invention is reduced to prac tice, and as the principles of the invention are capable of expression in various other structural arrangements it is to be understood that the invention may be practiced in any manner or form not inconsistent with its scope as claimed.

In the drawing:

Figure l is substantially a front elevation of a truck having a flexible cover equipped with the 55 invention.

Figure 2 is substantially a vertical longitudinal section therethrough, partly in elevation.

Figure 3 is an elevation of one of the ventilators as viewed from the interior of the cover.

Figure 4 is a section on the line 4-4 of Figure 3.

Figure 5 is a section on the line 5--5-of Figure 3.

The enclosed carrier vehicle 6, as here illustrated, comprises a truck having its body behind the drivers compartment enclosed by a flexible fabric cover I of a known type, such as the Dux-bak produced by the Crawford-Austin Manufacturing Company, of Waco, Texas, waterproof and impervious to passage of air, mounted on a known construction of frame 8 carried by the sideboards 9. With exception of the ventilating means to be described the cover and frame mount is, by way of example, the Dux-bak dome truck cover and frame manufactured by the hereinbefore stated Crawford-Austin Manufacturing Company.

As such covers when secured in position render the covered interior practically air-tight, there is no escape for the toxic, and sometimes fatal, exhaust gas fumes sucked in under the rear flap H], or for the dirt and dust, which objectionable entry arises by virtue of the rear end suction produced by the vacuum created behind the vehicle when in forward motion.

In order to break such vacuum and to insure proper ventilation within the covered body I provide the cover with ventilating means, preferably at a plurality of points, by which air is admitted to the interior and by which, when the vehicle is in forward motion, the admitted air is passed as a forced draft from front to rear to discharge beneath the rear flap. Although not essential to proper functioning, it is preferred that the ventilators be located in the front wall H of the cover as the air pressure is greater at the front than at any other point when the truck is in forward motion. Figure 1 illustrates the location of two such ventilating means having the general designation l2.

Each such ventilating means comprises a triangular aperture l3 cut in the cover by a V- shaped incision, the resultant flap [4 being 1nfolded along the triangle base l5 which provides one edge of the aperture, the flap being secured by attachment to the cover wall inwardly of the line of fold, preferably by a line of stitching l6 parallel to and spaced from the line of fold comprising the base I5.

In order to prevent ravelling and for rein- V forcement, the edges constituting the sides n of the triangular aperture 13 and which converge to the apex 18 thereof are inturned and hemstitched as at [9.

Cooperating with the aperture 13, and on the inner face of the cover wall portion, is a substantially semi-cylindrical conduit 20 arranged with its longitudinal axis perpendicular to and bisecting the base edge I5 of the aperture, the side edges 2! of the conduit being doubled inwardly for stiffening and being secured to the cover wall'portion by lines of stitching 22.

The conduit is so mounted that oneend portion23 thereof overlies the aperture I 3, said end portion being of somewhat rounded V-shaped form axially beyond the ends of the parallel side edges 2! with its tip 2d axially aligned with the aperture apex I8. At its other end the edge of r the conduit is perpendicular to the side edges 2| 1 and the material is doubled on itself and stitched to provide a marginal bead 25 which by virtue of its stiffening action assists in maintaining its semi-cylindrical cross-sectional form.

As shown best in Figure 3, the baflie end portion 23 is directed at an angle with respect to V the cover wall portion, the converging end edges 25 and the tip-24 being doubled in and secured to the cover by lines of stitching 2'!.- The mate rial of the bafile end portion 23 is gathered in two 9;; e 26 and converge in the axis of the conduit at a pleats 28 which extend inwardly from the edges aperture, as illustrated in Figure 4, the juncture of the'inner ends of the pleats and their combined stiffening action having a pronounced ridging effect on the material of the conduit which effectively serves to maintain'it against collapse so that at all times the tubular passage remains open and unobstructed from end to end.

Although the conduit 28 maybe constructed of any suitable materialand be substantially inflexible in character, it is preferred that it be of the same material as the cover. The outlet end defined by the marginal bead 25 is spaced from the inlet end as defined by the aperture I3, the extent .of spacing being determined by the length of the conduit which, in all instances should be sufficient to place the inlet and outlet ends well out of registry transversely of the passage.

In the embodiment here illustrated the air passage conduits 20 are vertically disposed on 'the inner face of the front wall ll of the cover 65. position is self-draining, and will thus be prevented from entering the interior of the covered.

with the inlet apertures l3 being well below the outlet end portions25 so that rain and sleet entering the apertures will be trapped by the baffle end portion 23 which by reason of its'angled disbody. 7

The ventilators are so arranged that the apertures l3 will be clear of the truck cab structure, so as to beunobstructed, and so that they will be spaced above the front end gate and clear of the frame bows in orderthat the conduits may maintain their tubular form at all times. 1

It is a feature of the invention that the air conduits 2B inside the cover may be disposed in any desired manner as to direction and length whereby to position the air outlets at any desired points and thus insure a predetermined directional flow of air through the area encompassed by the cover, the air pressure created by forward motion of the vehicle setting up a forced draft circulation.

In the. illustrated embodiment the. conduits 20 are directed to dispose their outlets at the upper front of the enclosed truck body, so that the fresh uncontaminated air enters along the top of the body under a constant pressure while.

truck, not only precluding the possibility of exhaust gas and dirt contaminated air entering the enclosed interior but also decreasing power and fuel consumption by eliminating the drag of rearend suction. 1 V a If desired, covering flaps 30 may be provided on the exterior of the cover for substantially closing the apertures 13 when found desirable, as when travelling in sub-freezing weather. or passing through the now frequently encountered dust storms. These flaps may be secured in open or closed position by suitable fastening means 3!, such as turn buttons. f

Having thus described the invention, what is claimed is: V e

'1. In a flexible cover for truck bodies, interior ventilating means comprising a substantially tubular flexible material conduit secured throughout its extent to the inner face of the cover, means reinforcing said conduit against. collapse on the cover, said cover having an air inlet aperture in communication with an end of the conduit, said conduit having an air outlet, and the end portion of said conduit adjacent said inlet aperture being angled relative thereto.

2. In a flexible cover for truck bodies, in-V terior ventilating means comprising a substantially rectangular length of flexible material edge fastened throughout its length to the inner face of a portion of the cover and out of contact therewith except at the points of attachment, said cover having an air inlet aperture,

one .end of said length of material being gath-,

3. In a flexible cover for truck bodies, interior,

ventilating means comprising a flexible tubular conduit of substantially semi-cylindrical cross section secured along each side edge to the inner face of the cover, said cover having an air inlet aperture adjacent one end of the conduit,

said end of the conduit being edge fastened'to the cover along the adjacent edge portion of said aperture, said conduit end also having a substantially plane portion transversely of the conduit and diverging from the cover directly behind said aperture, said substantially plane portion having stiffening means reinforcing it against collapse, and the other end-of said conduit being.

open and in spaced relation from said air inlet aperture. V

4. In a flexible cover for truck bodies, a front cylindrical tubular conduit secured on the inner face of the cover throughout each side edge and one end, said cover having an air inlet aperture opening laterally into said end of the conduit,

the other end of the conduit being open, and said conduit having self-contained means preventing its collapse against the cover.

W'ILBUR F. CRAWFORD. 

